Monthly Archives: December 2012

Ever been at a cardiac arrest resuscitation where someone’s opening and closing drawers at great speed but failing to retrieve the drugs or equipment you’ve asked for urgently?

What if your resus trolley were designed by team of clinicians, engineers, and designers? Such a project was achieved through a collaboration between Imperial College London and the Helen Hamlyn Centre for Design, and the award-winning result was called the ‘Resus:Station’.

The trolley separates into three trolleys for airway, drugs and defibrillation, and circulation. The contents are visible from the outside.

Image from Pubmed Free Full Text Article

As well as improving access to equipment, the trolley can log the team’s actions during each resuscitation attempt. It can also provide an instant display of its readiness for use by recording the removal and replacement of each item.

In a randomised comparison with a standard resus trolley, a number of measures of efficiency and team performance were significantly better using the Resus:Station during simulated cardiac arrest resuscitations.

It appears to be specifically designed for cardiac arrest situations rather than ‘resus’ in its wider context. The most recent article (cited below) reports that a newer prototype is being developed prior to the manufacture of the final product.

BACKGROUND AND AIM: Inadequately designed equipment has been implicated in poor efficiency and critical incidents associated with resuscitation. A novel resuscitation trolley (Resus:Station) was designed and evaluated for impact on team efficiency, user opinion, and teamwork, compared with the standard trolley, in simulated cardiac arrest scenarios.

METHODS: Fifteen experienced cardiac arrest teams were recruited (45 participants). Teams performed recorded resuscitation simulations using new and conventional trolleys, with order of use randomised. After each simulation, efficiency (“time to drugs”, un-locatable equipment, unnecessary drawer opening) and team performance (OSCAR) were assessed from the video recordings and participants were asked to complete questionnaires scoring various aspects of the trolley on a Likert scale.

RESULTS: Time to locate the drugs was significantly faster (p=0.001) when using the Resus:Station (mean 5.19s (SD 3.34)) than when using the standard trolley (26.81s (SD16.05)). There were no reports of missing equipment when using the Resus:Station. However, during four of the fifteen study sessions using the standard trolley participants were unable to find equipment, with an average of 6.75 unnecessary drawer openings per simulation. User feedback results clearly indicated a highly significant preference for the newly designed Resus:Station for all aspects. Teams performed equally well for all dimensions of team performance using both trolleys, despite it being their first exposure to the Resus:Station.

CONCLUSION: We conclude that in this simulated environment, the new design of trolley is safe to use, and has the potential to improve efficiency at a resuscitation attempt.

Objective Various intracranial pathologies in traumatic brain injury (TBI) can help to predict patient outcomes.
These pathologies can be categorised using the Marshall Classiﬁcation or the Abbreviated Injury Scale (AIS) dictionary or can be described through traditional descriptive terms such as subarachnoid haemorrhage (SAH), subdural haemorrhage (SDH), epidural haemorrhage (EDH) etc. The purpose of this study is to assess the prognostic value of AIS scores, the Marshall Classiﬁcation and various intracranial pathologies in TBI.

Methods A dataset of 802 TBI patients in the Trauma Audit and Research Network (TARN) database was analysed using logistic regression. First, a baseline model was constructed with age, Glasgow Coma Scale (GCS), pupillary reactivity, cause of injury and presence/absence of extracranial injury as predictors and survival at discharge as the outcome. Subsequently, AIS score, the Marshall Classiﬁcation and various intracranial pathologies such as haemorrhage, SAH or brain swelling were added in order to assess the relative predictive strength of each variable and also to assess the improvement in the performance of the model.

Results Various AIS scores or Marshal classes did not appear to signiﬁcantly affect the outcome. Among traditional descriptive terms, only brain stem injury and brain swelling signiﬁcantly inﬂuenced outcome [odds ratios for survival: 0.17 (95% conﬁdence interval [CI]; 0.08–0.40) and 0.48 (95% CI; 0.29–0.80), respectively].
Neither haemorrhage nor its subtypes, such as SAH, SDH and EDH, were signiﬁcantly associated with outcome. Adding AIS scores, the Marshall Classiﬁcation and various
intracranial pathologies to the prognostic models resulted in an almost equal increase in the predictive performance of the baseline model.

Conclusions In this relatively recent dataset, each of the brain injury classification systems enhanced equally the performance of an early mortality prediction model in traumatic brain injury patients. The significant effect of brain swelling and brain stem injury on the outcome in comparison to injuries such as SAH suggests the need to improve therapeutic approaches to patients who have sustained these injuries.

A subset of patients from the 2008 Vasopressin and Septic Shock Trial (VASST) trial had invasive haemodynamic monitoring measurements from pulmonary artery catheters. These data have now been analysed, revealing that vasopressin was associated with a lower heart rate compared with norepinephrine (noradrenaline) alone, without significant difference in cardiac index or stroke volume index. However, there was significantly greater use of inotropic drugs in the vasopressin group compared with the norepinephrine group.

Tachycardia and high quantities of catecholamine infusion are both associated with mortality in sepsis. The authors discuss:

“The idea of decatecholaminization, reducing both endogenous and exogenous adrenergic stimulation, is now believed to be an important treatment strategy, and the use of beta-blockers in septic shock is being considered. The early use of vasopressin or speciﬁc V1a receptor agonists in early septic shock may be another possible treatment.”

This interesting post-hoc analysis may help further define the patients in whom vasopressin is to be considered, by those clinicians who are using it in septic shock. For those that aren’t, I wouldn’t worry about it.

BACKGROUND: Vasopressin is known to be an effective vasopressor in the treatment of septic shock, but uncertainty remains about its effect on other hemodynamic parameters.

METHODS: We examined the cardiopulmonary effects of vasopressin compared with norepinephrine in 779 adult patients with septic shock recruited to the Vasopressin and Septic Shock Trial. More detailed cardiac output data were analyzed for a subset of 241 patients managed with a pulmonary artery catheter, and data were collected for the first 96 h after randomization. We compared the effects of vasopressin vs norepinephrine in all patients and according to severity of shock (< 15 or ≥ 15 μg/min of norepinephrine) and cardiac output at baseline.

RESULTS: Equal BPs were maintained in both treatment groups, with a significant reduction in norepinephrine requirements in the patients treated with vasopressin. The major hemodynamic difference between the two groups was a significant reduction in heart rate in the patients treated with vasopressin (P < .0001), and this was most pronounced in the less severe shock stratum (treatment × shock stratum interaction, P =.03). There were no other major cardiopulmonary differences between treatment groups, including no difference in cardiac index or stroke volume index between patients treated with vasopressin and those treated with norepinephrine. There was significantly greater use of inotropic drugs in the vasopressin group than in the norepinephrine group.

CONCLUSIONS: Vasopressin treatment in septic shock is associated with a significant reduction in heart rate but no change in cardiac output or other measures of perfusion.

I was lucky to be accompanied through much of my emergency medicine training and specialist work in the UK by Bruce Armstrong. We shared many resuscitation cases together in hospitals and in prehospital care.

When preparing the team in resus, Armstrong used to appoint a ‘safety officer’. This could be a nurse or physician – it didn’t matter. Their role was to stay hands-off and be the eyes, ears, and mouth that would identify impending hazards and verbally intervene to thwart them.

This process seemed so natural that I rarely gave it a thought, but its glaring absence from every place I’ve worked since has only recently hit me.

Because my son goes swimming.

My three year old son attends a swimming class. There is usually one other child in the class. Recently a third child joined the class and I found myself getting uncomfortable. How could the instructor stay vigilant? What if while holding one child one of the others sank under water out of her field of view? My own obsessive reading about the limitations of human perception and cognition has convinced me that no-one can really focus on more than one thing at a time.

A friend of mine has coached kids at swimming so I asked him how they solve this. The answer was obvious – you rely on the life guards whose sole role is look out for everyone’s safety. Duh.

And then it came to me. Armstrong knew this all along. He got this idea from his prehospital experience working with fire & rescue crews and brought it into the ED. It didn’t occur to me that no-one else did this. It was just him.

Keen to explore whether anyone else had embraced this idea, I decided to go to the top when it comes to patient safety, and contacted Martin Bromiley. He told me he hadn’t come across the role in this specific setting, although did point out a great example from the BBC Documentary ‘Operation Iceberg’, in which ‘a group of scientists boarded an iceberg with someone watching over the big picture of polar bears and the berg cracking as well as fog etc’. Martin directed me to the Clinical Human Factors Group on LinkedIn, where interest was shown in the concept although it was apparent others haven’t come across it.

I went back to Armstrong to push him on further thoughts:

Yes a thought….in every other high risk environment they have a specific safety officer, whether it be nuclear industry, airline etc.

The role is specific not an add on to another role.

In healthcare we are seen as successful the more we do by one person. Think lean… think ‘efficiencies’ in the health service. Other industries focus on safety. Get safety right, your brand is safe and the public go with you. If you don’t put safety first it is only a matter of time before disaster strikes. In healthcare we have too many serious incidents. The time has come to believe in and practice safety in health care rather than ticking boxes and not applying CRM and human factors.

So here’s a proposed checklist for a Resuscitation Room Safety Officer. It’s a first draft to get the idea out there and start the conversation – just click the image below to enlarge. I’ve written (and used) checklists in resus before, but none specifically for a safety officer.

I would like to hear if anyone’s already doing this anywhere, and how it’s been working.

1. All communities should create and maintain a regional system of STEMI care that includes assessment and continuous quality improvement of emergency medical services and hospital-based activities. Performance can be facilitated by participating in programs such as Mission: Lifeline and the Door-to-Balloon Alliance.(Level of Evidence: B)

2. Performance of a 12-lead electrocardiogram (ECG) by emergency medical services personnel at the site of first medical contact (FMC) is recommended in patients with symptoms consistent with STEMI.(Level of Evidence: B)

3. Reperfusion therapy should be administered to all eligible patients with STEMI with symptom onset within the prior 12 hours. (Level of Evidence: A)

4. Primary PCI is the recommended method of reper- fusion when it can be performed in a timely fashion by experienced operators. (Level of Evidence: A)

5. Emergency medical services transport directly to a PCI-capable hospital for primary PCI is the recommended triage strategy for patients with STEMI, with an ideal FMC-to-device time system goal of 90 minutes or less.(Level of Evidence: B)

6. Immediate transfer to a PCI-capable hospital for primary PCI is the recommended triage strategy for patients with STEMI who initially arrive at or are transported to a non–PCI-capable hospital, with an FMC-to-device time system goal of 120 minutes or less.(Level of Evidence: B)

7. In the absence of contraindications, fibrinolytic therapy should be administered to patients with STEMI at non–PCI-capable hospitals when the anticipated FMC-to-device time at a PCI-capable hospital exceeds 120 minutes because of unavoidable delays.(Level of Evidence: B)

8. When fibrinolytic therapy is indicated or chosen as the primary reperfusion strategy, it should be administered within 30 minutes of hospital arrival.(Level of Evidence: B)

Class IIa

1. Reperfusion therapy is reasonable for patients with STEMI and symptom onset within the prior 12 to 24 hours who have clinical and/or ECG evidence of ongoing ischemia. Primary PCI is the preferred strategy in this population. (Level of Evidence: B)

2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction: Executive Summary: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines.Circulation. 2012 Dec 17. [Epub ahead of print]

Purpose Traumatic disruption of the pelvis can lead to significant morbidity and mortality. ATLS® guidance advocates temporary stabilisation or ‘closure’ of the disrupted pelvis with a compression device or sheet. We undertook a best evidence equipment review to assess the ease and efficacy of the application of two leading commercially available devices, the T-POD® and the SAM Pelvic Sling™ II.

Methods Fifty health care professionals and medical students participated in pelvic circumferential compression device (PCCD) education and assessment. Participants received a 10-min lecture on the epidemiology and aetiology of pelvic fractures and the principles of circumferential compression, followed by a practical demonstration. Three volunteers acted as trauma victims. Assessment included the time taken to secure the devices and whether this was achieved correctly. All participants completed a post-assessment survey.

Results Both devices were applied correctly 100% of the time. The average time taken to secure the SAM Pelvic Sling™ II was 18 s and for the T-POD®, it was 31 s (p ≤ 0.0001). Forty-four participants (88%) agreed or strongly agreed that the SAM Pelvic Sling™ II was easy to use compared to 84% (n = 42) for the T-POD®. Thirty-nine participants (78%) reported that they preferred and, given the choice in the future, would select the T-POD® over the SAM Pelvic Sling™ II (n = 11, 22%).

Conclusions The results of this study indicate that both PCCDs are easy and acceptable to use and, once learned, can be applied easily and rapidly. Participants applied both devices correctly 100% of the time, with successful application taking, on average, less than 60 s.

HIFU uses ultrasound to increase the heat within tissues at a specific area, causing local necrosis and cautery without injuring surrounding tissues. It is used to treat some cancers, but has shown promise in haemorrhage control. In animal studies it reduced or stopped bleeding in liver(2), spleen(3), and vascular injuries(4).

It has been proposed to offer a promising method for hemorrhage control in both civilivan and miltary trauma(5). Automated systems have been developed and tested that identify bleeding using Doppler ultrasound techniques that then allow targeting of the HIFU beam to the bleeding tissue(6). The United States Army has identified the need for a such systems and has designed a remotely operated robotic haemostatic system to save lives of soldiers. This was presented in 2006(7).

I would love to know where we are with this technology, and why nothing seems to have appeared about it in the literature for the last few years. If you have any information, please fill us in via the comments box.

A South American randomised controlled trial has demonstrated no improvement in mortality when traumatic brain injured patients had therapy targeted at keeping intracranial pressure below or equal to 20 mmHg as measured by an intraparenchymal monitor. The control group’s management was guided by neurologic examination and serial CT imaging(1).

Editorialist Dr Ropper summarises what we should do with this information well(2):

“[The authors]…do not advocate abandoning the treatment of elevated intracranial pressure any more than the authors of studies on wedge pressure reject the administration of fluid boluses in the treatment of shock”

BACKGROUND

Intracranial-pressure monitoring is considered the standard of care for severe traumatic brain injury and is used frequently, but the efficacy of treatment based on monitoring in improving the outcome has not been rigorously assessed.

METHODS
We conducted a multicenter, controlled trial in which 324 patients 13 years of age or older who had severe traumatic brain injury and were being treated in intensive care units (ICUs) in Bolivia or Ecuador were randomly assigned to one of two specific protocols: guidelines-based management in which a protocol for monitoring intraparenchymal intracranial pressure was used (pressure-monitoring group) or a protocol in which treatment was based on imaging and clinical examination (imaging–clinical examination group). The primary outcome was a composite of survival time, impaired consciousness, and functional status at 3 months and 6 months and neuropsychological status at 6 months; neuropsychological status was assessed by an examiner who was unaware of protocol assignment. This composite measure was based on performance across 21 measures of functional and cognitive status and calculated as a percentile (with 0 indicating the worst performance, and 100 the best performance).

RESULTS
There was no significant between-group difference in the primary outcome, a composite measure based on percentile performance across 21 measures of functional and cognitive status (score, 56 in the pressure-monitoring group vs. 53 in the imaging–clinical examination group; P=0.49). Six-month mortality was 39% in the pressure-monitoring group and 41% in the imaging–clinical examination group (P=0.60). The median length of stay in the ICU was similar in the two groups (12 days in the pressure-monitoring group and 9 days in the imaging–clinical examination group; P=0.25), although the number of days of brain-specific treatments (e.g., administration of hyperosmolar fluids and the use of hyperventilation) in the ICU was higher in the imaging–clinical examination group than in the pressure-monitoring group (4.8 vs. 3.4, P=0.002). The distribution of serious adverse events was similar in the two groups.

CONCLUSIONS
For patients with severe traumatic brain injury, care focused on maintaining monitored intracranial pressure at 20 mm Hg or less was not shown to be superior to care based on imaging and clinical examination

“To date, approximately one-third of the women who die during pregnancy remain undelivered at the time of death”

Guidelines recommend cardiac arrest in pregnant women beyond 20 weeks gestation should be treated with perimortem caesarean delivery (PMCD) commenced within 4 minutes of arrest and completed within 5. These time intervals come from two papers, neither of which is current or used robust review methodology.

To address this, an up-to-date fairly comprehensive review was undertaken of published cases of maternal cardiac arrests occurring prior to delivery. The primary outcome measures were maternal and neonatal survival to hospital discharge and the relationship between PMCD and this outcome.

The Arrests

94 cases were included in the final analysis.Most pregnancies were singleton (90.4%, n = 85) with an average gestational age at the time of the arrest of 33 ± 7 weeks (median 35, range 10–42).

The most common causes of arrest were trauma, maternal cardiac problems, severe pre-eclampsia and amniotic fluid embolism, together comprising about 70% of arrests; two thirds occurred in hospital.

The Outcomes

Overall, return of spontaneous circulation (ROSC) was achieved more often than not (60.6%) and overall survival to hospital discharge was 54.3%

Only 57 cases (75%) reported the time from arrest to delivery; the average time was 16.6 ± 12.5 min (median 10, range 1–60), with only 4 cases making it under the advocated 4-min time limit.

The study may be limited by recall bias, under-reporting and publication bias, but provides a more comprehensive evidence base on which to base resuscitation recommendations. The authors provide a useful warning against becoming fixated with the recommended four minute window, which may lead teams to fail to attempt a potentially life-saving intervention:

“Fixation on specific time frames for PMCD may not be ideal. It may be more important to focus on event recognition and good overall performance…. It may be wise to advocate a short time frame for performance of PMCD in order to achieve better outcomes; however, blanket endorsement of an unrealistic time frame may well create a defeatist attitude when that time frame cannot be met.”

AIM: To examine the outcomes of maternal cardiac arrest and the evidence for the 4-min time frame from arrest to perimortem caesarean delivery (PMCD) recommended in current resuscitation and obstetric guidelines.

DATA SOURCES AND METHODS: Review and data extraction from all reported maternal cardiac arrests occurring prior to delivery (1980-2010). Cases were included if they provided details regarding both the event and outcomes. Outcomes of arrest were assessed using survival, Cerebral Performance Category (CPC) and maternal/neonatal harm/benefit from PMCD. Outcome measures were maternal and neonatal survival.

RESULTS: Of 1594 manuscripts screened, 156 underwent full review. Data extracted from 80 relevant papers yielded 94 included cases. Maternal outcome: 54.3% (51/94) of mothers survived to hospital discharge, 78.4% (40/51) with a CPC of 1/2. PMCD was determined to have been beneficial to the mother in 31.7% of cases and was not harmful in any case. In-hospital arrest and PMCD within 10 min of arrest were associated with better maternal outcomes (ORs 5.17 and 7.42 respectively, p<0.05 both). Neonatal outcome: mean times from arrest to delivery were 14±11 min and 22±13 min in survivors and non-survivors respectively (receiver operating area under the curve 0.729). Neonatal survival was only associated with in-hospital maternal arrest (OR 13.0, p<0.001).

CONCLUSIONS: Treatment recommendations should include a low admission threshold to a highly monitored area for pregnant women with cardiorespiratory decompensation, good overall performance of resuscitation and delivery within 10 min of arrest. Cognitive dissonance may delay both situation recognition and the response to maternal collapse.

The highlight for me was Mr Jonny Morrison speaking on Resuscitative Emergency Balloon Occlusion of the Aorta (REBOA). He is a British military surgeon currently out in Texas studying balloon occlusion of the aorta on pigs. Looking at trauma deaths, the next unexpected survivors will come from the uncontrollable haemorrhage group (truncal and junctional zones). This is by no means a new technique – described in the 1950’s during the Korean War – but like the early Star Wars chapters, needed to wait for technology to advance to make it feasible. It has the effect of cross clamping the aorta which provides afterload support, increases cerebral and coronary perfusion and provides proximal inflow control – without the mess of a resuscitative thoracotomy and greater access.

The placement of the balloon is determined by the location of the injury (see photo) and falls into two zones. Zone 1 is the thoracic aorta and is used for truncal haemorrhage control, avoid Zone 2 where the celiac axis etc originates and Zone 3 is infrarenal, used for junctional bleeding and pelvic haemorrhage.

His studies have determined that for Zone 3 amenable bleeds balloon occlusion up to 60min is the optimal time. Any longer and the debt of the metabolic load is paid by increased inotropic support requirements. He also compared REBOA to the current standard treatment for junctional injuries, Celox™ gauze. If coagulation is normal then both treatments perform similarly, the benefit is seen in coagulopathic patients where REBOA outperforms the gauze.

Has REBOA been used on humans? Yes a case series of 13 – the technique improved the BP allowing time to get to definitive surgery (blogged here 2.5 years ago!).

The Zone 1 studies are looking at continuous vs intermittent balloon occlusion. The jury is still out as to which is better. With the intermittent occlusion (20min on, 1min off) there are inevitably some losses when the balloon is deflated, conversely the metabolic debt generated by continuous occlusion is too great in some also leading to deaths.

What was very clear is that for this technique to have an impact it must be delivered proactively and pre-hospital. The challenges that need to be overcome are access to the femoral artery and blind accurate placement.

Prof Karim Brohi brought the conference to a close with a summary of what we have learned about coagulation in trauma this year. Here are three things;

FFP is good but as 43% deaths due to trauma in the UK are secondary to bleeding and occur in the first 3hr we are failing our patients by administering the treatment on average at 2.5hrs.

Fibrinogen levels are low in coagulopathic trauma patients; we should give cryoprecipitate early and aim for Fib ≥2.0

And finally whilst TEG is recommended to guide treatment and can provide results within 5 min, there are some aspects of coagulation it does not detect i.e. fibrinolysis was only detected in 8% of coagulopathic trauma patients – when measured in the plasma it was then detectable in 80%.

These are the highlights of the 2012 London Trauma Conference. I hope this whistle stop tour through these days has been informative and though provoking. I can assure you telephone hacking was not used to bring you this information and to my knowledge is correct.

This is Lou Chan, roving reporter for Resus ME! signing off.

‘London raises her head, shakes off the debris of the night from her hair, and takes stock of the damage done. The sign of a great fighter in the ring is can he get up from a fall after being knocked down… London does this every morning.’